FreeBSD is a Unix-like operating system based on the 4.4BSD-Lite release from Computer Systems Research Group (CSRG) at the University of California at Berkeley. It runs on processors compatible with the Intel x86 family, as well as on the DEC Alpha, the UltraSPARC processors by Sun Microsystems, the Itanium (IA-64) and AMD64 processors. Support for the PowerPC architecture is in development. It is generally regarded as being quite reliable and robust.

FreeBSD has the following key features:

• Preemptive multitasking with dynamic priority adjustment to ensure smooth and fair sharing of the computer between applications and users.
• Multi-user facilities which allow many people to use a FreeBSD system simultaneously for a variety of things.
• Strong TCP/IP networking with support for industry standards such as SLIP, PPP, NFS, DHCP, and NIS.
• Memory protection ensures that applications (or users) cannot interfere with each other. One application crashing will not affect others in any way.
• FreeBSD is a 32-bit operating system (64-bit on the Alpha, Itanium, AMD64, and UltraSPARC) and was designed as such from the ground up.
• The industry standard X Window System (X11R6) provides a graphical user interface (GUI) for the cost of a common VGA card and monitor and comes with full sources.
• Binary compatibility with many programs built for Linux, SCO, SVR4, BSDI and NetBSD.
• Thousands of ready-to-run applications are available from the FreeBSD ports and packages collection.
• Thousands of additional and easy-to-port applications are available on the Internet. FreeBSD is source code compatible with most popular commercial UNIX® systems and thus most applications require few, if any, changes to compile.
• Demand paged virtual memory and ``merged VM/buffer cache'' design efficiently satisfies applications with large appetites for memory while still maintaining interactive response to other users.
• SMP support for machines with multiple CPUs.
• A full complement of C, C++, Fortran, and Perl development tools. Many additional languages for advanced research and development are also available in the ports and packages collection.
• Source code for the entire system for you to control over your environment. Why be locked into a proprietary solution at the mercy of your vendor when you can have a truly open system?
• Extensive online documentation.

FreeBSD is released under the BSD License, which allows everyone to use and redistribute FreeBSD as they wish, as long as they do not remove the copyright notice and the BSD license itself (which does not prohibit re-distribution under another license).

Related Terms: Unix, TCP/IP, C, C++

Reference Links:
http://www.freebsd.org: All about FreeBSD
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/: FreeBSD Handbook